header{
  width: 100%;
  position: fixed;
  top: 0;
  height: 0.88rem;
  line-height: 0.88rem;
  background-color: #3190e8;
  color: #ffffff;
  text-align: center;
  font-size: 0.32rem;
  z-index: 9999;
}
.backIcon{
  position: absolute;
  left: 0.2rem;
}